Android operating system: history, architecture and evolution

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El Android OS It has become the heart of most mobile phones on the planet. It's in budget phones, high-end models, watches, TVs, cars, and even devices we can't even imagine. Behind that simple appearance lies a massive platform with a fascinating history, a complex technical architecture, and a constantly growing developer community.

Over the years, Android has changed radicallyIt started as a virtually unknown project, went through versions with candy names, made the leap to Material Design, consolidated itself as the absolute market leader, and is now experiencing a stage marked by... Artificial IntelligenceSecurity and integration with all types of connected devices. Let's take a calm and detailed look at what Android is, how it works internally, how it has evolved version by version, and what direction it's taking.

What is the Android operating system and how does it work internally?

Android is a mobile operating system based on the Linux kernel and a set of open-source software components. It is primarily designed for touchscreen devices, such as smartphones and tablets, but has also been adapted to watches (Wear OS), televisions (Android TV), cars (Android Auto and Android Automotive), IoT devices and other less common formats.

At the center of it all is the Android Open Source Project (AOSP)Android is the open-source project maintained by Google that serves as the foundation for all versions of Android. Manufacturers add their own customization layers to this core, such as One UI (Samsung), MIUI/HyperOS (Xiaomi), ColorOS (OPPO), or EMUI (Huawei), while the community creates alternative ROMs like LineageOS or GrapheneOS.

The Android architecture is organized in several layers. At the base is the linux kernelThe kernel handles memory management, processes, security, hardware drivers, and the network stack. Above the kernel is the Hardware Abstraction Layer (HAL), which provides a uniform interface for accessing elements such as GPS, cameras, modems, and sensors, without applications needing to worry about the specific details of each chip.

Above the HAL are located the native libraries in C and C++ which provide key functions: Surface Manager for the graphical interface, the OpenCore-based media engine, the SQLite database, the OpenGL ES graphics API for 2D and 3D, the WebKit rendering engine, the SSL and Bionic libraries, and the lightweight implementation of the C standard library used by Android. The complete system totals around 12 million lines of code, distributed among XML, C, Java and C++.

On top of these libraries runs the Android runtimeUp to Android 4.4.3, the virtual machine responsible for running applications was Dalvik, with just-in-time (JIT) compilation. Starting with Android 4.4, Android Runtime (ART) was introduced, and since version 5.0, ART has been the sole runtime environment: it compiles Java bytecode upon app installation (AOT, ahead-of-time) for improved performance and reduced battery consumption.

The top layer is formed by the application framework and the apps themselves. The framework offers the developers The same APIs used by the system to manage notifications, windows, services, content, sensors, and connectivity. The design is modular: any application can expose components (activities, services, content providers) that other apps can reuse, always respecting security restrictions.

Main components and technical features of Android

The user primarily sees the applications that come standard: phone, contacts, SMS, email, calendar, browser, maps, camera, gallery, clock, etc. All of them are written in Java or Kotlin (or in C/C++ via the NDK for specific parts) and packaged in APK files, which can be installed from stores like Google Play or manually.

Android includes a wide range of reusable libraries C/C++ libraries that support graphics, audio, video, storage, and connectivity. These libraries are not only used by the system but are also available to developers through the framework, so an app can access, for example, the SQLite database or GPU graphics acceleration without worrying about low-level details.

Each application runs on its own isolated process with its own virtual machine instance (Dalvik in older versions, ART in modern ones). This insulation, combined with the permission system And the per-app user model, which it inherits from Linux, creates a security barrier that prevents one app from freely accessing another's data without explicit authorization.

In terms of hardware, Android supports a long list of sensors and peripherals: Cameras for photos and videos, multi-touch capacitive screens, GPS, accelerometers, gyroscopes, magnetometers, light and proximity sensors, barometers, gamepads, and GPU acceleration both in 2D and 3D. All of this is managed from the kernel and the HAL, and exposed to the user through the framework.

In terms of connectivity, the platform offers support for GSM/EDGE, GPRS, CDMA, EV-DO, UMTS, HSDPA, HSPA+, LTE, WiMAX, Wi-Fi, Bluetooth, NFC and even newer technologiesIt also allows tethering, that is, sharing the mobile data connection with other devices via Wi-Fi, USB or Bluetooth.

The multimedia section is particularly comprehensive. Android is capable of playing WebM, H.263, H.264/MPEG-4 AVC, MPEG-4 SP, AMR, AAC, HE-AAC, MP3, MIDI, Ogg Vorbis, WAV, JPEG, PNG, GIF and BMPFor streaming, it supports RTP/RTSP, progressive download in HTML5 and, through plugins or third-party solutions, other protocols such as RTMP or Microsoft Smooth Streaming.

The development environment is currently based on Android StudioThe official IDE includes emulators, debugging tools, performance analysis, and code assistants. Previously, development was primarily done with Eclipse and the ADT plugin, but the entire platform has migrated to Google's solution, which offers direct SDK integration, Gradle build tools, and support for Java, Kotlin, and C/C++.

Google Play, APK and app ecosystem

Google Play is the official Android app storeFrom there, users can download free or paid apps, games, books, movies, and other content simply by linking a Google account. Payment can be made by card, PayPal, or gift cards, and Google shares the revenue with the developers, who receive approximately 70% of the amount.

The applications are distributed in the format APK (Android Package)An APK is a compressed file containing the app's code, resources, manifest, and native libraries. Any file explorer can install an APK if the user enables installation from unknown sources, which has led to the emergence of alternative app stores like the Amazon Appstore, Aptoide, F-Droid, and SlideME.

F-Droid is a special case: it is a completely open source app storeThis applies both to the client and the applications it distributes. This makes it an attractive option for those who prefer to avoid proprietary software or want to review the code before installing anything.

In recent years, Google has strengthened security controls on Google Play with Play ProtectThis system analyzes installed apps and those downloaded from the store to detect malicious behavior. Although Android is not free of malware, most threats are distributed from repositories of dubious reputation and not from the official store.

In addition to applications, the ecosystem includes services such as Google Play ServicesThis is a set of components that Google updates directly from the App Store, independent of operating system versions. Thanks to this strategy, many new features (Maps APIs, synchronization, security, push notifications with Firebase Cloud Messaging, etc.) reach older devices without requiring a full system update.

History of Android: from unknown startup to world leader

Android Inc. was founded in October 2003 In Palo Alto, California, Andy Rubin, Rich Miner, Nick Sears, and Chris White started the company. Initially, their goal was to create an advanced operating system for digital cameras, but they soon realized that the truly interesting market was in smartphones, which were just beginning to take off.

In July 2005, Google bought Android Inc. for an estimated $50 million. Rubin and his team moved to Google, where they began working on a flexible, updatable Linux-based mobile platform that manufacturers could adopt without paying licensing fees. From the outset, the idea was to create an open-source platform that would compete with Symbian, Windows Mobile, and later, iOS.

On November 5, 2007, the Open Handset Alliance (OHA)A consortium of hardware, software, and telecommunications companies, including Texas Instruments, Broadcom, Nvidia, Qualcomm, Samsung, Intel, LG, Motorola, Sprint, and T-Mobile, was formed. Android 1.0 was officially announced at the same time, although the first commercially available mobile phones didn't arrive until 2008.

The first Android phone available to the public was the HTC Dream, also known as T-Mobile G1, launched on October 22, 2008. It had a touch screen, a slide-out physical keyboard and was responsible for debuting an interface that, although it seems primitive today, represented a radical change for the time.

Over the years, Google has been promoting its own devices under the family Nexus (Nexus One, Nexus S, Galaxy Nexus, Nexus 4, Nexus 5, Nexus 6, Nexus 7, Nexus 9, Nexus 10) to showcase the "pure" vision of Android. These models typically received new versions before anyone else and served as a benchmark for manufacturers.

At the same time, traditional manufacturers began adopting Android. In 2014, for example, Nokia unveiled the Nokia X, X+ and XL with a customized version based on AOSP, although that experiment was short-lived. Mass adoption came mainly from Samsung, HTC, LG, Sony, and later, Chinese giants like Huawei, Xiaomi, and OPPO.

Android versions and main new features

For many years, each version of Android had a code name for dessert or sweet in alphabetical order. Although since Android 10 Google has used only numbers publicly, internally gastronomic code names still exist.

The first iterations (Android 1.0 Apple Pie and 1.1 Banana Bread laid the foundation for the platform. Cupcake (1.5) introduced the virtual keyboard and the ability to upload videos to YouTube, Donut (1.6) expanded resolution and network support, and Eclair (2.0-2.1) brought GPS navigation and multi-account synchronization.

With Froyo (2.2) Performance was improved and support for Adobe Flash was added, while Gingerbread (2.3) It refined the interface, optimized power consumption, and revamped game and sensor management. Honeycomb (3.x) was a tablet-specific version that experimented with a different interface designed for larger screens.

Ice Cream Sandwich (4.0) It unified the design between mobile phones and tablets, introducing a much cleaner and more modern look. Subsequently, Jelly Bean (4.1-4.3) It polished performance with the Project Butter initiative, which sought smoother animations, and improved the notification system.

KitKat (4.4) It optimized Android for devices with limited memory, gave greater prominence to Google Now, and strengthened voice recognition. This version solidified Android's presence in low-end and mid-range devices, further expanding its global reach.

With Lollipop (5.0-5.1)Introduced in 2014, Material Design arrived, a much more colorful and consistent visual language that redefined Android's appearance. The definitive switch to ART as the sole runtime was also made, improving performance and energy efficiency.

Marshmallow (6.0) It introduced the new runtime permissions system and Doze mode, which extends battery life by limiting background activity when the device is idle. Nougat (7.0-7.1) It added split-screen functionality, improved notifications, and refined support for multiple windows.

Oreo (8.0-8.1) It was a turning point internally thanks to Project TrebleA modular architecture that separates the vendor layer (drivers and HAL) from the rest of the system to facilitate updates by manufacturers. Android Oreo Go Edition also appeared, a lightweight version for devices with less than 1 GB of RAM, Picture-in-Picture mode, and notification channels. Furthermore, integration was strengthened. Google Play Protect, which automatically checks installed applications to stop malware.

At (9.0)Launched in 2018, it opted for the Artificial intelligence to manage battery and predict app usageIt introduced features such as Adaptive Battery, Adaptive Brightness and App Actions, and launched Digital Wellbeing, a set of tools to control mobile phone usage time and reduce dependence.

Android 10Apple, which publicly abandoned dessert-themed names, brought system-wide dark mode, new privacy controls, gesture navigation, and improvements for foldable devices and 5G. It also strengthened app isolation and location controls.

Android 11 focused on better organizing the conversations (specific section in the notifications), improve controls for connected devices (home automation) and refine Project Mainline, the initiative that allows system updates via Google Play. It also added "one-time only" location permissions and more advanced support for 5G, foldable phones, and modern codecs like animated HEIF.

Android 12Released in late 2021, it introduced Material You, a major redesign that adapts the interface colors to the wallpaper. Among its new features are... Privacy Panel, where you can see which apps have recently accessed the camera, microphone or location, new gestures, App Pairs to manage split windows and features such as using your mobile as a digital car key.

Android 13Released in 2022, the update refined personalization (adaptive icons, more themes), improved the media player, and expanded digital wellbeing options. In terms of privacy, apps now request more granular permissions to access each file type (photos, videos, audio), notifications require explicit permission, and the The clipboard is cleared automatically. After some time, support for Bluetooth LE Audio also arrived.

Android 14Available in stable form since October 2023, this update has focused on optimizing performance, further improving battery management, and strengthening security and privacy features. It includes stricter permission controls, tools for malware protection, and smoother integration with smart home devices and wearables. Multitasking has been refined, and system resource usage has been improved.

Beyond version 14, Android continues to advance along the lines of delve deeper into artificial intelligence, personalization, and securityNewer generations increasingly incorporate generative AI features, advanced notification filters, scam detection mechanisms, and tools to better control the exposure of our data.

Android 16 and the new wave of AI features

In the most recent iterations, such as Android 16Google is clearly committed to more frequent system updates, starting with its own Pixel devices. This version includes smart notification summaries that condense long conversations or complex messages into a quick and easy-to-review view.

Another novelty is the automatic notification organizerThis feature groups and silences lower-priority alerts (promotions, news, social media notifications), reducing noise and allowing users to focus on what truly matters. All of this is supported by AI models capable of understanding the basic context of the messages.

Android 16 also expands the options of interface customizationYou can choose specific icon shapes, apply a wider variety of themes, and force darkening of light-colored apps that don't have a native dark mode. The idea is that everyone can customize their phone to their liking without having to install too many extra tools.

In the family sphere, the new section of parental control It allows you to set screen time limits, schedule downtime periods, restrict the use of certain apps, and apply other rules to monitor how children use their Android devices.

Alongside these system-specific features, Google has released features for the entire Android ecosystem. For example, Call ReasonThis feature allows you to mark a call as "urgent" so the recipient sees it upon receiving it, and if they don't answer, it will appear in the call log with that indication. Expressive Captions, which generates subtitles with emotion tags such as or , designed to better understand the tone of videos and posts even without sound.

The management of group chats The system has been strengthened: if an unknown number invites a user to a group, Android displays an alert with key information so the user can quickly accept, leave, or block/report the number. In Chrome, pinned tabs now work the same as on desktop, remaining visible at all times.

The function Circle to Search It has been enhanced with the ability to analyze suspicious messages: by highlighting the content, an AI-generated summary indicates whether it might be a scam. In terms of accessibility, voice dictation with TalkBack has been improved (for example, initiating dictation in Gboard with a double tap of two fingers) and has been integrated Gemini to write and edit text using natural commands.

Other improvements include a more advanced version of Guided Frame On Pixel phones, the camera not only indicates if there's a face in the frame, but also describes in more detail what the camera sees, and you can start Voice Access by saying "Hey Google, start Voice Access" without touching the phone. Connecting hearing aids has also been simplified with Fast Pair, which makes pairing hearing devices from brands like Oticon, Sonic, and Bernafon much easier.

Security, privacy, and criticism of Android

Being a very widespread and relatively open platform, Android has been a prime target for researchers and attackersA 2013 Symantec study pointed out that, paradoxically, iOS accumulated many more serious vulnerabilities than Android, although the number of attacks in practice was higher on Android due to its popularity and the ease of installing apps from external sources.

Over time, Google has tightened its measures security and permission controlRuntime permissions, restrictions on background execution, default storage encryption, boot checks, stricter sandboxing, and the aforementioned Play Protect platform have all been introduced. Even so, much of the responsibility lies with the user, who must avoid installing applications from dubious sources.

In terms of privacyAndroid has received criticism for the amount of data that can be shared with Google and other players in the advertising ecosystem, and for its management of authentication mechanisms. Leaks in 2013 and 2014 also revealed that agencies such as the US NSA and the UK's GCHQ had developed capabilities to intercept information from Android devices, including SMS messages, location, emails, notes, and data from popular apps like Angry Birds.

It was also discovered that some devices stored location information when the option was activated. "Using wireless networks" In the location section, this led to comparisons with iPhone behavior. However, on Android, this data is used as cache and is deleted when the option is disabled, not as a permanent record.

On the other hand, Android has been struggling for years with the problem of fragmentationThere are thousands of models with different manufacturers, operating systems, processors, and levels of support. This means that many older versions remain active, not all phones receive the latest updates, and security patches are not rolled out uniformly.

Google once tried to establish a commitment from manufacturers to provide updates for at least 18 months, but that plan was never effectively implemented. Part of the problem stems from the proprietary drivers which chip manufacturers and suppliers do not release, making it difficult to keep older devices running modern versions of the system.

The philosophy of frequently updating hardware and the constant release of new versions that are not always optimized for older devices have led some analysts to point to Android as one of the factors driving the scheduled obsolescence in the world of smartphones.

Devices, architectures and market share

Although we usually associate Android with mobile phones, the system is used in a huge variety of electronics devices: laptops, netbooks, tablets, Android TVs, Wear OS watches, TV receivers, car infotainment systems (Android Auto and Android Automotive), headphones and many other connected devices.

The predominant hardware architecture is ARMBut there is also support for x86 through initiatives like Android-x86, and Google TV, for example, uses a version adapted for that platform. This has allowed Android to run even on conventional computers and test machines.

In terms of adoption, Android has led the global mobile operating system market for years. By 2018, it had already surpassed 90% of the fee If all smartphones were counted, Android would still dominate in 2024 with around 70,1% global market share compared to iOS's 29,2%. The difference is even more pronounced in countries like India (around 95% market share for Android) and Brazil (over 80%), while iOS is dominant in markets like the United States and Canada.

It is currently estimated that there are over 3,6 billion Android users worldwide, compared to approximately 1,46 billion iOS users. A significant portion of the Android device market comes from Chinese manufacturers, who together account for over 55% of sales, with Samsung and Xiaomi as leading players.

Looking at usage by version, the figures from April 2025 place Android 14 Android is the most widespread version, with around 33,4% of the total, followed by Android 13, 12 and 11. Older versions such as 10, 9 Pie or 8 Oreo are still present, although with decreasing percentages, and there are still remnants of systems as old as Lollipop in circulation.

Regarding the activation rate, Android has gone from 100,000 devices per day in 2010 to hundreds of millions of activations per year. In 2013, the milestone of 1 billion active Android smartphones was reached, and since then the figure has continued to grow, accompanied by the rise of Asian manufacturers and the expansion into new product categories.

Application development and business model

One of the keys to Android's success is that Anyone with reasonable programming skills can develop an appThe Android SDK is free to download, the tools are cross-platform, and the main language (Java, along with Kotlin) is widely used.

In addition to Java and Kotlin, developers have the NDK (Native Development Kit) To write parts of the code in C or C++, which is useful for games, graphics engines, or tasks that require very high performance. There are also visual environments like App Inventor for beginners, and cross-platform frameworks based on web technologies or technologies like Flutter, React Native, or Qt thanks to projects like Necessitas.

The applications are packaged in APK format and uploaded to the Play Store or other stores, where Google gives back 70% of its revenue to developers of integrated sales and purchases. This combination of accessibility in development and monetization potential has created an ecosystem with millions of apps on almost every topic: productivity, social networking, banking, health, education, home automation, games, etc.

In terms of payments, Android integrates Google Pay (successor to Android Pay), which allows you to pay with your mobile phone at contactless terminals as long as the device has NFC and runs at least Android 4.4. This service competes with solutions like Apple Pay or Samsung Pay and relies on the large installed base of Android.

From a business perspective, Android is considered one of the most successful business models In the world of modern software, Google does not charge a license fee for the system, but rather earns revenue primarily from advertising, Play Store purchases, and associated services, which has driven its widespread adoption across all price ranges and regions.

Visual identity, branding and design evolution

The Android logo was originally designed with the Droid typographyCreated by Ascender Corporation, the iconic green robot, popularly known as "Andy," was designed by Irina Blok and has become one of the most recognizable symbols in the technology sector.

The robot's characteristic color is a specific green whose hexadecimal reference is #3DDC84as outlined in the Android Brand Guidelines. This color has been used for years in campaigns, promotional materials, and interfaces, with slight variations depending on design trends.

Regarding system fonts, Android has evolved. During the Ice Cream Sandwich era, the following was introduced: RobotoRoboto, a typeface designed to improve readability on high-resolution screens. With Lollipop (5.0), Roboto was redesigned, and in 2018, with Android 9 Pie, Google began using Google Sans in more interface and branding elements.

In 2023 the logo was also updated, changing from writing "android" in lowercase to "Android" with a capital letter, and minor adjustments were made to the strokes to better align it with the overall aesthetic of Google products.

In parallel, the system's design language has evolved from Holo (in the early modern versions) to Material Design, and then to Material You, where the customization of colors and shapes The user experience is the main focus. This is complemented by the ability to change launchers, icons, and themes, something highly valued by those who enjoy fine-tuning their phone's appearance.

This entire journey shows how Android has gone from being an experiment by a small startup to becoming the dominant mobile platformPresent on billions of devices and in a vast array of formats, its Linux-based architecture, the open AOSP model, the power of its app ecosystem, and the flexibility it offers to manufacturers and users explain much of its success, but also bring challenges such as fragmentation, security, and privacy management. The path it is taking, with the increasing importance of artificial intelligence, modular updates, and the strengthening of control and customization tools, points to an operating system that will remain a key component of everyday computing for many years to come.